<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        ul {
            width: auto;
            height: 40px;
            background-color: aqua;
            white-space: nowrap;
            overflow-y: hidden;
            overflow-x: scroll;
            display: flex;
        }
        
        ul::-webkit-scrollbar {
            display: none;
        }
        
        .dd {
            flex-shrink: 0;
            list-style: none;
            height: 40px;
            width: 50px !important;
            margin-right: 20px;
            background-color: blueviolet;
        }
    </style>
</head>

<body>
    <ul>
        <li class="dd">1</li>
        <li class="dd">1</li>
        <li class="dd">1</li>
        <li class="dd">1</li>
        <li class="dd">1</li>
        <li class="dd">2</li>
        <li class="dd">4</li>
        <li class="dd">3</li>
        <li class="dd">3</li>
        <li class="dd">3</li>
        <li class="dd">3</li>
        <li class="dd">3</li>
    </ul>
</body>

</html>